G8JNJ
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Priyom.org is a good place to look up number station schedules on their main page. More info on New Star from Taiwan https://priyom.org/number-stations/other/v13 Regards, Martin
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Hi John, Yes it would be fantastic if it acted as though you opened the DX label filter panel. I'd assumed that it would be possible to combine this with the existing data base selection option. I wasn't aware of the existing URL parameter dx=[012] …
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WRT "LZ1AQ dual-loop system. This is set up so that I can switch between the 2 loops, or to sum them together (my usual default mode). <snipped> I have this set up in my attic of a 2-storey house in an urban area, and generally it works w…
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Hi Artur, The original poster has already got an LZ1AQ loop setup, which is likely to be considerably better than the MLA-30, which IMHO is pretty badly designed and not really up to the task. I have reverse engineered a MLA-30, and also made extens…
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"I need to keep my attenuation adjusted enough to avoid having he Kiwi overloaded during the day when 770 is on and 900 is on day power." Have you tried adding some external notch filters or an equalisation network ? Regards, Martin
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Here's one of mine that I'd dare to show you. This is laid out on a sheet of MDF so that it can be wall mounted. https://forum.kiwisdr.com/uploads/195/AYWC9I0CAEXD.png It's always best to start off with good intentions, as it soon gets messy... ht…
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Hi Frank, Here's a quick snapshot. https://forum.kiwisdr.com/uploads/576/DP7Y9Y5RC6JH.png I moved the position of the DC-DC convertor box around until I got the least spurs and interference when the RF input was terminated with a 50 ohm load. It end…
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OK don't worry, it was only to try and better understand a problem I encountered. I think it is due to a mismatch between directory structures. I was trying to copy a KiWi DX config across to a Flydog with a corrupted config, and back again to valid…
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This old thread my be of interest if you are planning to use the GPIO port for antenna switching. https://forum.kiwisdr.com/index.php?p=/discussion/comment/7539 If you wish to better protect your KiWi and also reduce radiated noise, then adding some…
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I'd say the D series looks like a possibility, especially the part with the sharp impedance peak at around 200MHz, but that's just my opinion. In addition to the impedance it presents, it will also alter the rise time of the data and clock signals, …
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Hi John, WRT "Anyway, maybe the thing to do is add series resistors to all the SPI signals. They can be populated with 0R jumpers if there are any problems." Good idea, and it would also allow you to try some in-line SMD ferrites. I note t…
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Hi John, Just some random thoughts for further discussion. My opinion is still that in many cases, it is strong local medium wave broadcast stations that cause the majority of problems, especially when the antenna is a broadband active loop, and tha…
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Hi Steven, Thanks for the detailed information regarding the device topology. That has answered a lot of the questions I had, and is more reassuring for use in this particular application. Regards, Martin
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Hi Steven, Interesting. I saw that the input power de-rating curve falls quite sharply on frequencies lower than 15MHz, and is not projected any lower than 2MHz. This made me wonder if the IMD performance would also be degraded on these lower freque…
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To be honest it's quite difficult to tell from the SNR scores alone, however the day / night variation is a good indicator especially on the upper HF bands. This is my equivalent plot to yours. I've used Black Cat Systems KiWi SDR monitor to produce…
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The inclusion of a balun is an attempt to resolve some of the more common issues that have been encountered with KiWi installations, that are associated with antenna and KiWi ground paths. The balun will not significantly affect the KiWi's performan…
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Try my home KiWi. http://g8jnj.zapto.org:8073/?ext=ant_switch Note that any changes you make will affect all users
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https://forum.kiwisdr.com/index.php?p=/discussion/comment/16536#Comment_16536 I don't think the chokes would contribute anything further. Stray capacitance between placement of the coax cable and case is likely to be a much more significant factor …
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That is very odd. It sounds like intermittent network connectivity, but I assume it works OK when you use it as a normal receiver. Are you using a local network connection ? The serial number can be found on the Network tabbed page. Regards, Martin
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Part of the discussion regarding the choice of input transformer is its performance WRT common mode rejection, which is pretty much defined by its interwinding capacitance (the lower the better). Don't become fixated by the insertion loss at very lo…
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Hi Ken, I believe the message means that your router has not been configured to allow connections to the KiWi from the outside world via your ISP. When you say you were just using it, I assume you mean just using it on your own personal local networ…
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I'd suggest checking R136 on the BB board. It is near the Ethernet connector and provides a very low ohm link between the digital and RF grounds. When I have accidentally connected +5v to the KiWi Ground in the past, by accidentally touching the +5v…
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Hi John, If you are doing this, any chance of a one channel as wide as possible bandwidth channel ? It would come in very handy for occasional I/Q captures of some of the more exotic wideband digital modes. Only if it's not too difficult though. Re…
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Excellent news :-)
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"How does any SNR test differentiate a "real" signal from a spurious carrier?" It doesn't, but it's better than nothing. My request was in order to save time and effort when selecting KiWi's from the map for TDoA runs. In my expe…
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Interesting. Unless I'm mistaken all the animated plots seem to start at 09:50. Which is a about an hour after the event in my last image. There have been several other events during the day but none quite as spectacular. Regards, Martin
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The antenna is a 20m per side terminated vertical delta loop fed at the apex approx 20m agl running South West / North East. It is on a hilltop site in a rural area, overlooking the Southern coast of the UK. http://wessex.zapto.org:8073 - 0-30MHz …
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"Any port in a storm! lol. Beautiful image." Surely - Any port in a Solar storm :-) A few more type II this morning. Here's a nice faster waterfall capture with drift and strong second harmonic. https://forum.kiwisdr.com/uploads/650/UECT…
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It's interesting that the accusation is that you should have implemented various critical backup and support systems, when in fact they are using an unpaid for, voluntary, hobbiest system for their supposedly "critical safety of life" purp…
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It's also a lengthy letter / rant, with a verbose series of personal titles which is usually a good indicator of how seriously you should take it. Another thought. Ask him for his ISP details so that you can "investigate his concerns" and …